This paper describes an algorithm for reconstructing and identifying a highly collimated hadronically decaying τ-lepton pair with low transverse momentum. When two τ-leptons are highly collimated, their visible decay products might overlap, degrading the reconstruction performance for each of the τ-leptons. A dedicated treatment attempting to tag the τ-lepton pair as a single object is required. The reconstruction algorithm is based on a large radius jet and its associated two leading subjets, and the identification uses a boosted decision tree to discriminate between signatures from τ+τ- systems and those arising from QCD jets. The efficiency of the identification algorithm is measured in Zγ events using proton–proton collision data at s=13 TeV collected by the ATLAS experiment at the Large Hadron Collider between 2015 and 2018, corresponding to an integrated luminosity of 139fb-1. The resulting data-to-simulation scale factors are close to unity with uncertainties ranging from 26 to 37%.
Reconstruction and identification of pairs of collimated τ-leptons decaying hadronically using s=13 TeV pp collision data with the ATLAS detector
Primomo L.;Panizzo G.;Monzani S.;Giugliarelli G.;Giordani M. P.;Cobal M.;
2025-01-01
Abstract
This paper describes an algorithm for reconstructing and identifying a highly collimated hadronically decaying τ-lepton pair with low transverse momentum. When two τ-leptons are highly collimated, their visible decay products might overlap, degrading the reconstruction performance for each of the τ-leptons. A dedicated treatment attempting to tag the τ-lepton pair as a single object is required. The reconstruction algorithm is based on a large radius jet and its associated two leading subjets, and the identification uses a boosted decision tree to discriminate between signatures from τ+τ- systems and those arising from QCD jets. The efficiency of the identification algorithm is measured in Zγ events using proton–proton collision data at s=13 TeV collected by the ATLAS experiment at the Large Hadron Collider between 2015 and 2018, corresponding to an integrated luminosity of 139fb-1. The resulting data-to-simulation scale factors are close to unity with uncertainties ranging from 26 to 37%.| File | Dimensione | Formato | |
|---|---|---|---|
|
s10052-025-14075-3 (2).pdf
accesso aperto
Tipologia:
Versione Editoriale (PDF)
Licenza:
Creative commons
Dimensione
4.73 MB
Formato
Adobe PDF
|
4.73 MB | Adobe PDF | Visualizza/Apri |
I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.


